Silicate-based glasses currently used as coatings for some types of orthopedic implants have shortcomings that frequently lead to debonding. The primary goal of this project will be the development of a new family of borate-based glass coatings. Our basic hypothesis is that borate glasses can be tailored to be bioactive and strongly adhere to metal implants, thereby overcoming debonding and particulate debris, a major cause of implant loosening and failure. The project proposed here will involve fabrication and testing of about twenty-four different formulations of borate-based glass. Testing of basic properties of these glasses will include measurements of thermal expansion, glass transition and glass crystallization temperatures, dissolution, and XRD surface analysis. Concomitant in vitro cell culture assays with hFOB 1.19 human osteoblast cells will be performed to assess the biocompatibility of the glasses. About one-third of the glasses will be selected for additional tests. The second groups of tests will include infrared reflectance analyses to test formation of a bioactive carbonated hydroxyapatite layer plus measurement of the kinetics of proliferation and SEM morphology of hFOB cells cultured on the glass surface. The most promising two or three of these glasses will be selected for final evaluative tests of glass bonding to metal substrate and expression of osteoblast phenotype markers (alkaline phosphatase and osteoclacin) by hFOB cells cultured on the glasses. A companion goal pursued in conjunction with the research will be to train students as future investigators possessing a rare combination of skills in materials science and biological sciences critical to development of new and more effective biomaterials.